﻿//////////////////////////////////////////////////////////////////
//
// Triangle.cs
//
// Copyright (c) 2012 Dan Pike.
//
// Permission is hereby granted, free of charge, to any person
// obtaining a copy of this software and associated documentation files
// (the "Software"), to deal in the Software without restriction,
// including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software,
// and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

namespace Geometry
{
   public class Triangle
   {
      ////////////////////////////////////////////////////////////////////////
      //
      public Triangle(Point3D argA, Point3D argB, Point3D argC)
      {
         a = argA;
         b = argB;
         c = argC;
      }

      ////////////////////////////////////////////////////////////////////////
      //
      public Point3D[] vertices
      {
         get { return new Point3D[] { a, b, c }; }
      }

      ////////////////////////////////////////////////////////////////////////
      //
      public Triangle[] into4
      {
         get
         {
            // Split into four triangles by bisecting each side (see triangles.jpg)
            Point3D d = a.Add(b).Mul(0.5f);
            Point3D e = a.Add(c).Mul(0.5f);
            Point3D f = b.Add(c).Mul(0.5f);

            return new Triangle[]
            {
                 new Triangle(a, d, e)
               , new Triangle(d, b, f)
               , new Triangle(d, f, e)
               , new Triangle(e, f, c)
            };
         }
      }

      ////////////////////////////////////////////////////////////////////////
      //
      public Point3D a;
      public Point3D b;
      public Point3D c;
   }
}
